1. Field of the Invention
The present invention relates to a pipe joint locking device for preventing accidental loosening of a pipe joint after tightening.
2. Description of the Related Art
In a pipe joint, a joint member having an internal thread (cap nut) is tightened onto a joint member having an external thread and, as a result, the joint member having the external thread and a pipe member are connected while facing each other through a seal portion. As a locking device (locking clamp) for preventing accidental loosening of the pipe joint after tightening, there is a device, as disclosed in Patent Document 1, formed of: a first clamping member including mounting portions to be mounted while prevented from relative rotation to engaging portions (wrench flats) provided to a joint member having an external thread and a coupling portion provided to be contiguous with the mounting portions and to be brought into contact with an outer peripheral face of the joint member having the internal thread from one side, and a second clamping member having a coupling portion to be brought into contact with the outer peripheral face of the joint member having the internal thread from the other side, the coupling portion of the first clamping member and the coupling portion of the second clamping member being coupled through the joint member having the internal thread.
Patent Document 1: Japanese Unexamined Patent Publication No. 8-105580